10 Minute BidsPaint calculatorGallons and 5-gallon buckets.
Enter the exterior wall area, or each room inside. Pick your coats and coverage, and add primer if you need it. You get gallons, rounded up, and how many 5-gallon buckets that is.
Your estimate
—
| Walls | — |
|---|---|
| Ceilingslength × width | — |
| Wall paint | — |
| Buy | — |
| Ceiling paint | — |
| Buy | — |
| Primer | — |
| Buy | — |
How we got it
Skip the math — upload your plans. We measure it all on a 3D model of your house.
Priced per plan setPainting bid, 3D model included
Upload your plansDoors and windows are left in, so the count errs a little high. To trim it, take off about 20 sq ft for each door and 15 sq ft for each window. Rough siding, stucco and bare wood soak up more paint: use a lower coverage.
This is an estimate from the numbers you enter. It doesn't see surface prep: patching, sanding, stain blocking, or siding and trim that arrive unprimed. Check the label and confirm on site before you buy.
The paint formulas.
-
Area
Outside, the walls you will paint. Inside, the four walls of each room, and the ceiling if you paint it.
room walls = 2 × (length + width) × height · ceiling = length × width -
Gallons
Every coat covers the whole area again.
gallons = area × coats ÷ coverage, rounded up -
Primer
One coat.
primer gallons = area ÷ primer coverage, rounded up -
Buckets
Big areas go in 5-gallon buckets, the rest in single gallons.
buckets = gallons ÷ 5; the rest in gallons
Worked example2,000 sq ft of siding, 2 coats at 350 sq ft a gallon: 2,000 × 2 ÷ 350 = 11.43, so 12 gallons: two 5-gallon buckets and 2 gallons.
| Wall area | 1 coat | 2 coats |
|---|---|---|
| 500 sq ft | 2 | 3 |
| 1,000 sq ft | 3 | 6 |
| 1,500 sq ft | 5 | 9 |
| 2,000 sq ft | 6 | 12 |
| 2,500 sq ft | 8 | 15 |
| 3,000 sq ft | 9 | 18 |
Gallons rounded up. Doors and windows left in.
Skip the math —upload your plans.
We build the house in 3D from your plan set and measure walls, trim, soffits and doors, inside and out. Your painting bid prices them by the gallon and the hour. You spend about 10 minutes checking it against your plans.
Priced per plan setPainting bid, 3D model included
Or see what’s in a painting bid.
Paint questions.
How much does a gallon of paint cover?
About 350 square feet a coat on smooth, primed walls is typical, and the label gives the maker's number. Rough siding, stucco and bare wood take more paint, so use a lower coverage for them.
How many coats of paint do I need?
Two coats is typical for new work or a color change. One coat can refresh the same color in good shape.
Do I need primer?
Prime new drywall, bare wood, patches and stains, or a big color change. One coat of primer covers about 300 square feet a gallon; check the label.
Do I subtract doors and windows?
This calculator leaves them in, so it errs a little high. To trim the count, take off about 20 square feet for each door and 15 square feet for each window.
Is this an exact paint order?
No. It's an estimate from the numbers you enter. Surface prep, patching, stain blocking and rough or porous surfaces change what you use. Check the label and confirm on site before you buy.